Electric equipment for mining machines



April 11,1933. N. D. LEVIN ET AL I ELECTRIC EQUIPMENT FOR MINING MACHINES original Filed Oct. 18, 1928 an S r&

Patented Apr. 11, 1933 YJUNITED STATES PATENT. OFFICE 'NILS D. LEVIN AND JOHN SFBELTZ, F COLUMBUS, OHIO, ASSIGNORS TO THE JEFFREY ..MANUFACTURING COMPANY, OF COLUMBUS, OHIO, A CORPORATION OF OHIO ELECTRIC EQUIPMENT FOR MINING MACHINES Original application filed October 18, 1928, Serial No. 313,323. Divided and this application filedDecember 4, 1929; Serial No. 411,654; Renewed'March 19, 1932.

g The-present inventionrelates to certain new and 1 useful improvements in electric equipment for IIllIllIlg machines; and especial-.

1y to an improved arrangement of parts forming the electric circuits oflocomotives, selfpropelling trucks, and similar apparatus adapted for use in coal minesfsubject to the accumulation of explosive gases in the work j mg rooms of the mine.

The especial object of this invention is to provide-a locomotive, or other mining apparatus, adapted to receive its actuating'electric current from a naked trolley wire in the usual ind we'llknown manner, when traveling-along the entries of the mine, or through a flexible conductor cable when operating in places subject to gas accumulations, and having automatically acting means to insure against l the formation of arcs exposed to contact with the gaseous atmosphere of the mine.

A'further object is to provide in apparatus of the classdescribed such-an arrangement of parts that the operator will at all times be fully protected from electric shock. 2-5

I Themeans' whereby we-attain these and other'objects are fully set forth in the following specification and illustrated in the ac:

companying drawing which is' a diagram of the electric circuits of a locomotive embodying our present invention, the several elements of themachine being indicated by appropriate symbols. 1

As heretofore constructed such apparatus have possessed certain inherent defects which seriously restrict their use 1n coal mines sub- -'ject to accumulations of explosive gases.

Motors, controllers, switches, fuses and the like, have been enclosed in explosion proof casings, and the supply of actuating current has been maintained through flexible conductor cables connected with the supplyconductors of the mine in a manner-and at points conducive-to safety.- It has heretofore been customary and convenient to' arrange the motorcontrolling devices between the supply conductors and the motor-in order that the electric circuits may be disconnected from line potential to thereby'protect the operator when making-adjustments and'repairs. By this arrangement there is full "line potential between the electrical parts of the controller and its supporting frame and casing'which, beingattached directly to the frame of the machine and consequently'with the ground,

produces a tendency to destructive short circuits.

Explosive mixtures of gases are T seldom encountered'in the main haulage entries of a mine because of the strong current'sjof air flowing therethrough. The-use of naked trolley wires, contacting trolley wheels, and

ground returns through the rails of the mine track is therefore permissible in these portions of a mine, and because of their conven- 313,323,; filed October 18th, 1928', of which this application is a division, claims were presented to a system for the transmission 'ofelectricity to a vehicle, and other claims were presented relating to a motor control system. In that application we have elected to prosecute the claims relating to the motor control system and in response to the requirement for division have presented the present application containing claims relating to the system for the transmission of electricity to a vehicle.

In the drawing we have diagrammatically shown a locomotive having two motors adapted to propel the machine along the rails of a mine track. As here shownthe motors comprise the armatures l and 2 and the field coils 3 and 4 which are connected by suitable conductors with a controller hav- 3 ranged in the main conductors of the circuits, and each is provlded with an actuating C011 18, 19, 20, 2 1 and 22 respectively, arranged to close their respective switches. Two overload relays having switch members 23 and 24 arranged in the control circuit of the switches 16 and 17 are provided with coils 25 and 26- in series with the motor circuits and are energized by excessive currents therein to open their respective switches. Resetting coils 27 and 28 are also provided to reclose the switches 23 and 24.

Having now described the general arrangement of parts we will point out more particularly the features of improvement which characterize our invention.

hen the trolley wheel 8 is placed in contact with the trolley wire 9 connection is established through the conductor 29 with the switch 15 which normally stands open. Gurrent flowing through the conductor 30, the actuating coil 20 and the conductor 31 to ground 32 formed on the frame of the locomotive, energizes the coil 20 to close the switch 15 sending current through the conductor 33, overload coil 25 and conductor 34 to the switch 16 whichstands normally open. At the same time current flowing through the conductor 35, actuating coil 18.

and conductor 36 to the ground 32 energizes the coil 18 to close the switch 13 establishing connection between the ground 32 through the conductor 37 the terminal 38 of the controller, the blow-out magnet 39 and the contact finger 40 with the contact segment 41 of the commutating cylinder 5 with which said finger is in permanent connec-' tion. The finger 42 of the controller is connected by a conductor 43 through the resetting coils 27 and 28 of the overload relay to establish connection with the main positive conductor 33. When the controller cylinder is moved in the starting direction the finger 42 contacts with the corresponding segment 44 of the commutating cylinder to complete the circuit and energize the coils 27 and28 to cause the switch blades 23 and 24 to be moved to their closed position. This 7 establishes a connection between the positive conductor 33 through the switch members 23 and 24, the .conductor45, the actuating coils 21 and 22 of the switches 16 and 17, and

the conductor 46 to the finger 47 of the controller. A further movement of the commutating cylinder 5 establishes connection between the finger 47 and the contact seg ment 48 to complete the circuit to energize the coils 21 and 22 to close the switches 16 and 17 thereby establishing connection through the conductor 49 between the main positive conductor 29 and the finger J of the reverse cylinder of the controller. It is to be noted that the contact segment 48 is of such proportion that connection is maintained between it "and the finger 47 in all operative positions of the commutating cylinder, and that by this connection the coils 21 and 22 are continuously energized to maintain the switches 16 and 17 in closed position. WVhen the commutating cylinder 5 is turned in the reverse direction interrupting the connection between the finger 47 and the contact segment 48 the two switches 16 and 17 simultaneously open thereby dividing the arc and reducing the tendency to injury of the contact members. It is also to be noted that the proportions of the contact segments 41 and 71 are such that contact is not broken between these segments and the brushes 40 and 72 when the controller cylinder is moved to the off position, and the intermediate segments so overlap that the resistance circuit is never broken, thereby avoidingthe formation of electric arcs in the controller.

When the reverse cylinder 6 is in position to cause the contact plates in the row marked PA to engage the appropriate fingers, connections will be established by which the motors are arranged in parallel, their armatures revolving in a direction to propel the locomotive ahead. When the reverse cylinder 6 is turned to a position to cause the contact plates in the rowmarked SA to engage the appropriate fingers, connections will be established by which the motors are arranged in series, their armatures revolving in a direction to propel the locomotive ahead. lVhen the reverse cylinder 6 is turned to a position to cause the contact plates in the row marked. SR to engage the appropriate fingers, connections will be established by which the motors are arranged in series, their armatures revolving in a direction to propel the locomotive rearwardly, or reverse. When the reverse cylinder 6 is turned to a position to cause the contact plates in the row marked PR to engage the appropriate fingers, connections will be established by which the motors are arranged in parallel, their armatures revolving in a direction to propel the locomotive in reverse.

ance in the. circuits of the motor to control the speed of rotation of their armatures. As such devices are well understood in the mining machine art further description is not thought to be required at this time.

Further rotation of the commutatmg cylinder 5 connects more or less resist- Whenthe "locomotive is tobeoperated a mine room, or snnllar locat1on, and must derive its actuating current through the flexible-conductor cable 11 the-conductor: 50 is connected by asuitable hook 51 with the trolley wire 9, and the-conductor 52 is -connected bya suitable hook 53 with the: track rail 54 in the entry thereby -establish ing connection fromthe trolley wire 9 through the conductor 50, positive connec-i 1 tion 55 of the cable reel,-and theconductor 1 56 'tothe switch 14 ;which stands normally I -open. At the same time connections are es-n tablished from the track-rail 54 through the conductor 52 the negative connection of the cable reel 57, the conductors 58 and 37 to o the terminal 38, blow-outcoil 39'andgfingerl 40 of the commutating cylinder 5 of the cont-roller. When the trolley wheel '8 is removed from contact-with the trolley wire 9, current is'cut off from theconductors and -thereby de-energizing-the coils 18' and 20 permitting the switches 13 and 15 t0-v e2'5- open. The switches 13, 14 and 15 are pref erably provided with interlocking-mechanism such that when the switches 13' and 15 are closed the switch '14 is locked open" and 1 when the switch 14 is closed the switches 13 and '15'are'locked open; B'y-this arrange- =ment we have assured the exclusion of-electrio potential from the locomotive frame 32 close the switches Hand 17 in the'main and from the naked trolley'wheel8 while current is being received-through the flexible conductor cable 11, afl'ording added in suranceagainst accidental shortcircuit between thenaked trolley wheel and the machine frame, or shock to, the operator.

When the commutating cylinder 5 "is moved inthe starting directioncontact is established, asbefore described; between thefinger 42 andcontact plate 44 assuring the closing of the switch blades 23 and 24. Fur-- ther movementof thecommutating cylinder .5 establishes :conneetion between thefinger- 47 and segment 48 to complete the circuit through the actuatingv coils 21 and 22 to tive conductors.

tact. plate 59 adapted, when the reverse cyl inder is in either the serie'sahead or series 19 and the conductor 64 with the main nega-'-; 'tive' conductor 58 thereby completing the the flexible conductor cable 11. To: insure ,s'uch operation we have provided upon the reverse cylinder6 of the controller aconreverse position, tocontactwith the fingers 60 and 61. The finger 60 islconnected by a conductor 62 with the, main positive con ductor 56, and the finger 61 is connected through the conductor 63, the actuating coil circuit whereby theactuating-coillQ is en- Jergized to' close the-switch l4," completing :travelingin the reverse direction'and when current is being received through the flexible-conductor cable 11. To insure such operation we have provided a, contact plate 65 upon the reverse cylinder'so'positioned that when the cylinder stands in the series reverse position the contact fingers 66 and 67'will be connected; The finger 66 is connected by a conductor 68 with the main negative conductor 37 and the finger 67 is connected through the conductor 69, the motor 12, conductors 70 and'62 to the main positive conductor 56 thereby establishing a circuit tor energizing of the motor 12.

f What we claim is: v

1. In an apparatus of the'class described, the combination with ametallic 'framenormally connected with one side of-an electric supply circuit, of a motor mountedthereon,

a-trolley-mounted on'sa'id frame and adapted to-contact with a conductor of the opposite side otsaid electric supply circuit, means to connect one side of said motor with said trolley, meansto connect the other side of said motor with said frame, meansconnected between said motor and said frame to control the=actuation of said-motor, means connected between SZlIdIIlOlJOI' and said trolley and controlled by said controlling-means to'interrupt the flow of currentto'said motor, a 'pair of conductors adapted to respectively to be connected with the opposite sidesof said electric tsupply circuitgandmeans to transfer the connections of said connecting means from said trolley-and said frameto-said co-nductors'as r and for thepurpose set forth. posii 2. In an apparatus of the class described,

7 the combination'with 'a metallic frame nor- 1 Because of the danger of injury to the cable 11 resultingyfrom theoperation of the locomotive at excessive speed, itis de-- mally connected'with oneside of an electric supply circuit,'of a motor-inounted thereon,

a trolley mountedon said frameand adapted to contact with aconductor of the'opposite sideof said electric'supply circuit, means to connect one side of said motor with'said troh ley,-uncans-toconnect the other-side of said motor with said-frame, means connected between said motorand said frame to' control the actuation ofsaid motor, means connected between said motor and said trolley and con trolled by said controlling means to interrupt the flow of current-to said motor, a pair of conductors adapted respectively to be connected with the opposite sidesof said electric supply circuit, and automaticallyacting means to transfer the connections ofsaid co-nnecting means from said trolleyfand said frame to said conductors as and for the purtroller mounted on the frame and including.

pose set forth.

3. In a machine of the class described, the combination with a frame, of supporting wheels therefor, amotor mounted upon said frame and operatively connected with said wheels, a flexible conductor cable adapted to be connectedwith a supply conductor to supply actuating current to said motor, acona reversing drum to control the actuation of the motor to propel the machine in either direction, a cable reel on said frame upon which said conductor cable is windable, areel motor on said frame, an operating circuit for said motor, and a switch in said circuit closed only when the reversing drum is in reverse position.

4. In a machine of the class described, the

.combination with a frame, of supporting wheels therefor, a motor mounted upon said frame and operatively connected with said wheels, a flexible conductor adapted to be connected with a supply conductor to supply actuating current'to said motor, a controller mounted on the frame and including a reversing drum to control the actuation of the motor to propel the machine in either direction,

a cable reel on said frame upon which said conductor cable is windable. a reel motor on said frame, an operating circuit for said motor including bridging means on the reversing drum, said bridging means being operative only when the drum is in reverse position.

5. In a machine of the class described, the combination with. a frame, of supporting wheels therefor, a plurality of motors mounted upon said frame and operatively connected with said wheels, a controller mounted on said frame and including a reversing drum to control the actuation of the motors to pro-,

6. In a machine of the class described, the.

combination with a frame, of supporting wheels therefor, a plurality of motors mounted upon said frame and operatively connected with'said wheels, a controller mounted on I said frame and including a reversing drum to control the actuation of the motors to propel the machine in either direction, said drum having series and parallel reverse and series and parallel ahead positions, a flexible conductor cable adapted to be connected with a supply conductor to supply current to said motors, a cable reel on said frame upon which said conductor cable is windable, a reel motor on said frame, an operating circuit for said motor including bridging means on the reversing drum, said bridging means being 0perative only when the drum is in series reverse position. 1 a l 7 In a machine of the class described, the combination with a frame, of supporting wheels therefor, two electric motors mounted on said frame and operatively connected with said wheels, a trolley mounted on said frame adapted to contact with a conductor of the electric supply circuit, a flexible conductor adapted to be connected with said electric supply circuit, and controlling devices adapted to connect said motors in either series or parallel with said trolley or in series only with said flexible conductor and to cause their actuation to propel the machine in either direction as and for the'purpose set forth.

8. In a machine of the class described, the combination with a frame, of supporting wheels therefor, a plurality of electric motors mounted on said frame and opera-tively connected with said wheels, a trolley mounted on said frame and adapted to contact with an electric supply conductor, a flexible conductor cable adapted to be connected with the supply conductor, a controller including a reversing drum having series and parallel positions for-placing the motors in circuit with the trolley, and circuit connections for con necting said conductor cable with the motors, said connections including switching means closed only when the reversing drum is 1n series position.

, 9. In a machineof the class described, the combination with a frame, of supporting wheels therefor, a plurality of electric motors mounted on said frame and operatively connected with said wheels, a trolley mounted on said frame and adapted to contact with an electric supply conductor, a flexible conductor cable adapted to be connected with the supply conductor, a controller including a reversing drum having series and parallel positions for placing the motors in circuit with the trolley, and circuit connections for connecting said conductor cable with the motors, said connections including a bridging plate on the reversing drum and operative only when the drum is in series position.

10. In anelectric locomotive having a plurality of motors,a controller for connecting the motors in series or parallel for either forward or reverse drive of the locomotive, feeding means for the motors including a trolley and means other than the trolley, means for completing a trolley circuit to the motors when the controller is in either series or parallel position, and means for completing a circuit to the motors through said other 7 through said cable operative only when the controller is in series position.

12. In an electric locomotive having a plurality of motors, a controller for connecting the motors in series or parallel, a controlling resistance connectible in the motor circuit when the motors are in series or in arallel, feeding means for the motors inclu ing a trolley and a reel cable, means for completing a trolley circuit to the motors when the controller is in either series or parallel position, and means for completing a circuit to the motors through said cable operative only when the controller is in series position.

13. In an electric locomotive having a plurality of motors, a controller for connecting the motors in series or parallel, feeding means for the motors including a trolley and a reel cable, means for completing a trolley circuit to the motors when the controller is in either series or parallel position, and a switch operated by the controller only when in series position to complete a circuit to the motors through said reel cable.

14. In an electric locomotive having a plurality of driving motors, a controller for connecting the driving motors in series or parallel for either forward or revese drive, feeding means for the motors including a trolley and a cable, a reel on which the cable is wound, a reel motor, means for completing a circuit to the driving motors through said cable operative only when the controller is in series position, and means for completing a circuit to the reel motor operative only when the controller is in series reverse posi tion.

15. In an electric locomotive having a plurality of driving motors, said motors having distinct slow and fast speed ranges both for- Ward and reverse, feeding means for the motors including a trolley and a reel cable, means operative to complete a circuit to the motors through the trolley for slow and fast speed drive, and means operative to complete a circuit to the motors through the cable for slow speed drive only.

16. In an electric locomotive having a plu= rality of motors, a controller for connecting the motors in series or parallel, feeding means for the motors including a trolley and a reel cable, an electromagnetic switch in the cable circuit, an energizing circuit for closing said. switch to complete said cable circuit, means for completing a trolley circuit to the motors when the controller is in either series or parallel position, and bridging means on the controller operative to complete said energizing circuit only when the controller is in series position.

In testimony whereof we have hereunto set our hands.

NILS D. LEVIN. JOHN S. BELTZ. 

